Organsims and evolution - 3 Flashcards
what are the benefits of parental investment?
- increased number of offspring
- increased chance of survival
- increases the evolutionary fitness of parent
why are eggs larger than sperm?
more energy is needed to produce them are they are an energy store
how do sessile organisms reproduce?
- self-fertile (self pollination)
- synchronised spawning
- use of another organism to carry gametes
will an r-selected species produce many or few offspring?
produce many offspring
in what sort of environment are r-selected organisms most successful?
in unstable environments
which type of organisms have the greatest chance of offspring survival - r or K selected?
K selected
what is polygamy?
when each individual may mate with several others in the same reproductive season
what is monogamy?
when each individual only shares gametes with one other individual
what can sign stimulus produce?
can produce a specific fixed-action pattern response in another individual (to do with mating)
what can be influenced by sexual imprinting in early life?
mate choice - may chose mates that resemble parents
what does imprinting increase?
increases fitness through natural selection
what is sexual dimorphism?
difference in characteristics between male and females in same species
what is reversed sexual dimorphism?
when characteristics of males and females are opposite to the usual
why will male compete with each other?
for the ability to mate with females
what are sneakers/satellite males?
weaker males that superficially resemble the female to avoid male-male rivalry
